OK now up to the Sturmpanzer IV Brummbär, a the unit 033 has a steel armor on the hull side of 4 were all others have 3, 3 seems correct unless the skirts should add something to the Steel armor too and not only to the HEAT armor.
If the info is correct the Sturmpanzer IV was produced in 4 series.
1st Series(60 tanks) had the possibility to mount an MG34 on the open gunner hatch.
2nd Series(60 tanks) used the Ausf. H chassis and removed that hatch so I assume the chance to mount an MG was also removed.
3rd Series(unknown amount) only had minor changes, the biggest being a periscope instead a view port for the driver and the lighter version of the gun.
4th Series(unknown amount) used the Ausf. J chassis and added a ball-mounted MG(you can see this here:
http://upload.wikimedia.org/wikipedi...6/SdKfz166.jpg).
I would suggest to add the AAMG to the early versions(ID 033 & 722) and remove the AAMG on the late versions(ID 871 & 872).
And if it can be confirmed that there was a version completely without MG than a mid version that covers series 2 & 3 should be added, but I guess with a database so full it will be a problem.
I'm not sure about the entry dates, the production started in April 43 but they did not seem to reach the front before June 43 so if that is used for the entry date I guess June/43 seems OK, just as July 44 does for the 4th series(late versions) that started production in June 44 and so surely reached the frontlines not before July.
BTW I guess lowering the Fire Control and Range Finder values to zero for the units used as artillery variants was done for a reason or?
PS I was still not able to find info whether or not the new 15cm L/12 had a different performance.